Study shows no link between Lyme disease and depression

Researchers who set out to clarify whether there is an association between Lyme disease and depression found that the prevalence of depressive symptoms was similar among infected and noninfected patients who sought care at a tertiary Lyme center.

Tizza P. Zomer, MSc,of the Lyme Center Apeldoorn at Gelre Hospital in the Netherlands, and colleagues said their findings suggest that depressive symptoms should not be used to help diagnose Lyme borreliosis (LB) in this setting.

“Published results on an association between depression and LB are contradictory,” they wrote in Clinical Infectious Diseases. “Compared to healthy controls, it remains unknown whether LB is associated with moderate/severe depressive symptoms. We demonstrated that when comparing patients with and without LB referred to a tertiary Lyme center, LB is not associated with depressive symptoms. This is relevant for settings where physicians discriminate for LB in clinical practice.”

The researchers examined serum samples and self-administered questionnaires collected from 1,454 patients (median age, 51 years; 51.2% women) who were treated at the Lyme Center Apeldoorn between January 2008 and December 2014 to compare the prevalence of moderate/severe depressive symptoms among those with and without LB. Overall, 30.1% of patients had no clinical LB and negative serology, 17.5% had no clinical LB and positive serology, 30% had clinical LB and negative serology, and 20.6% had clinical LB with positive serology.

According to the data, the prevalence of moderate/severe depressive symptoms was highest in patients with no clinical LB and negative serology (29.3%), followed by patients with clinical LB and negative serology (20.9%), those with clinical LB and positive serology (19.3%), and those with no clinical LB and positive serology (15.3%). The adjusted OR for depressive symptoms was 0.71 (95% CI, 0.50-1.03) among those with clinical LB and positive serology vs. those with no clinical LB and negative serology.

Although Zomer and colleagues said the large cohort strengthens the validity of their study, they noted several limitations. For example, patients may have had multiple subjective symptoms, predisposing them to depression. In addition, there were no data on whether patients with LB were depressed before being diagnosed. Nevertheless, the researchers concluded that their results demonstrate that depressive symptoms are common in patients treated at the tertiary Lyme center.

“To optimize care and treatment of patients suspected of LB visiting a tertiary Lyme center, we recommend patients be screened for depressive symptoms so that, if indicated, they can benefit from psychological referral,” the researchers wrote. – by Stephanie Viguers